Solid imaging systems typically create three-dimensional objects based upon computer data by forming sequential layers of material into cross-sectional patterns that are combined along a z-axis to form a three-dimensional object. Solid imaging systems include systems that build parts by one or more of the following techniques: stereolithography, laser sintering, fused deposition modeling, selective deposition modeling, film transfer imaging, and others.
Certain solid imaging systems provide solid imaging material in a trough with an actinic radiation transparent bottom through which actinic radiation can be projected to cure cross-sectional patterns of the three-dimensional object onto the photosensitive solid imaging material, thereby curing the material. A build pad and/or platform is vertically movable above the trough, and the three-dimensional object is typically supported by the build pad or platform such that the three-dimensional objects are generally built in an upside down manner. Examples of such solid imaging techniques and similar techniques are disclosed in U.S. Pat. Nos. 4,575,330; 5,391,072; 5,447,822; 5,545,367; 7,052,263; 7,614,866; 7,706,910; 7,845,930; and 8,003,040 and U.S. Patent Application Publication No. 2001/0048183, all of the disclosures of which are hereby incorporated by reference in their entireties.